Pass Labs Preamps with tube amps?

No, after my experience with Pass preamps(XP-20 and XP30), their sterile and lifeless characteristics, I would not compromise any decent amp, tube or sold state, with Pass preamps. My opinion and stated with no offense intended, those still hanging on to Pass preamps are kidding themselves. Tube preamps are the way to go! 

Friend had great success with Pass XP-22 preamp and Thor tube mono blocks....I always felt the Pass XP were a big step up from the X series

I have a Pass Labs XP-32 pre feeding an Air Tight ATM-300R (low power 300b tube amp).  All sounds great to me.  Best my system has sounded.  Detailed, but great natural timbre as well.

For what it’s worth, I also have a Pass Labs XA 25 solid state amp — relatively low power and very well reviewed.  The XA 25 sounds great with the XP-32 as well, but the Air Tight is much better (as it should be at a much higher price level than the XA 25).  My only point in making the comparison is that a Pass pre with a great tube amp can outperform a Pass pre matched to a good Pass solid state amp.

I have a lot of experience with Pass. They make great amps and ok preamps. This is like riding up the pacific coast highway on a bike South to North… against the wind all the way. 
 

To find a great preamp to match an amp, I would look to Audio Research, VAC, Conrad Johnson… then decide on your amp. 

I have aa Pass XP10 and Pass 250.8- and Audio research REF150SE amp and the LS28SE pre amp; speakers are Wilson Sasha 2. I switch around combinations of the gear every few months to save hours on the tubes in the ARC and or heat generation - sound. The Pass XP10 is good- quiet, built well and neutral sounding. I can't say it's very exciting or musical. More like a functional unit that neither adds no detracts from the music. I wouldn't look to use it as a pre on a tube amp, I think it'd limit the purpose of using a tube amp by being to neutral, almost dry sounding. I do suggest the reverse though- running a good tube pre amp like the ARC LS28SE or REF 5 into a solid state amp like the Pass - this combo sounds great.